Krug

Krug is the largest ground-based Russian SIGINT (signals intelligence) system. (Krug is Russian for "ring" or "circle"). The system consists of a circularly disposed Wullenweber array of broadband top-loaded vertically polarized monopoles. It is used for High-Frequency (HF) interception and directi on finding (DF). The original arrays were installed in the late 1940s and in the 1950s.

The aerial array in the original Krug system consisted of 40 vertical wideband antenna...